The present invention relates to a therapeutic agent. More specifically, the present invention relates to a physiologically active substance which is useful in a field of medicine and to the use of the substance.
Recently, attention has drawn to a mode of death of cells or tissues which is called as apoptosis (self-blasting or self-destruction of cells).
The apoptosis is a death that has been originally programmed in the genome of a cell, and is different from necrosis, which is a pathological cell death. Specifically, it is considered that the following processes lead to the death. The activation of a gene that programs the apoptosis triggered by certain external or internal factor(s) causes the biosynthesis of a protein of programming cell death. In some cases, a protein of programming cell death that exists in a cell in its inactive form becomes activated. The thus generated active protein of programming cell death destroys the cell.
Induction of the apoptosis in desired tissues or cells is very worthwhile because it makes it possible to eliminate unnecessary or harmful cells from a living body in a natural manner.
The main object of the present invention is to provide a substance having a physiological function such as an apoptosis-inducing activity which is useful in a field of medicine, and the use of the substance.
The present invention is outlined as follows. The first aspect of the present invention relates to a compound of general formula I: 
wherein X is OH or OSO3H, R is a substituent other than OH, the substituent being a substituent of which the elimination enables introduction of unsaturated bonds at 3-position and 4-position of 3,6-anhydrogalactose or a sulfated derivative thereof and/or a substituent having a tissue-specific affinity.
The second aspect of the present invention relates to a pharmaceutical composition containing the compound of general formula I as an active ingredient for treating or preventing a disease sensitive to the compound of general formula I.
The third aspect of the present invention relates to a food or a drink which contains, which is produced by diluting, and/or which is produced by adding thereto the compound of general formula I.